Bangladesh police on Saturday arrested seven opposition party members for a suspected arson attack on a train that killed at least four people, including children.

Bangladesh is set to hold a general election on Sunday, January 7, and the majority opposition party, the Bangladesh Nationalist Party (BNP), is boycotting.

Police said they had arrested a senior BNP leader from Dhaka and at least six others from the party's youth wing in connection with the arson.

Fire and civil defense services said that eight educational institutions and one Buddhist monastery have been torched among 14 arson incidents since Friday evening.

What to know about the fire on the train

The fire on the Benapole Express broke out around 9 p.m. (1500 GMT) on Friday as it was moving toward Dhaka's main railway station, Rakibul Hasan, a duty officer of the Fire Service and Civil Defense, told AP news agency.

Mahid Uddin, an additional police commissioner with the Dhaka Metropolitan Police, said the fire was "clearly an act of sabotage" to scare people ahead of the elections. He did not immediately name any suspects but said police would take action against those responsible.

The fire was brought under control by seven firefighting units after about an hour, fire service official Shahjahan Sikder said.

Polling booths also set on fire

Police added arsonists set fire to at least five primary schools, serving as polling station, in Gazipur on the outskirts of Dhaka.

Police suspected the arsonists had set fire to the schools in the middle of the night.

"We have intensified patrolling and remain on high alert to thwart any untoward incident," said Gazipur police chief Kazi Shafiqul Alam.

Last month protesters set a train ablaze, killing four people, during a countrywide strike called by the opposition.

Upcoming elections

Bangladesh is seeing a polarized political atmosphere between Hasina and former premier and opposition leader Khaleda Zia, who is currently under house arrest.

The main opposition Bangladesh Nationalist Party (BNP) is boycotting the elections, calling it a ploy by Prime Minister Sheikh Hasina's Awami League to legitimize a sham vote. If Hasina wins, it would be her fourth term in office.

The BNP has demanded Hasina's resignation and the appointment of a neutral authority to run the election, which she has refused. She has accused the party of inciting anti-government protests that have been taking place from October last year, and have killed at least 10.

Senior BNP official Ruhul Kabir Rizvi said the Benapole Express incident was "undoubtedly an act of sabotage and cruelty against humanity," but blamed the ruling party for it. 

Rizvi has urged people not to vote on Sunday and called for a 48-hour general strike beginning 6 a.m. on Saturday.

Police and paramilitary forces have been deployed to guard polling booths on Sunday. The army, navy and air force have also been deployed across the country for peacekeeping. 

rm, tg/msh (AP, Reuters)